Adult Oyster Density

Four people in wetsuits sit on buckets along the shoreline in front of white square quadrats, examining oysters.

Twice a year (spring and fall), biologists’ sample 15 haphazardly selected ¼-m² quadrats at each of the oyster reefs to assess adult oyster populations. All live oysters that fall within each quadrat are counted, as are the articulated shells (valves still attached) of dead oysters. This allows biologists to quantify the density of live and dead oysters on each reef and observe any changes in reef density and health. Measuring the size of a subset of the oysters counted allows biologists to make assessments about the age and overall status of the population.